Ohh that is the truth! Song's family already knows about Lihua's identity and hence they agreed to kill her. But Wei already liked her that time and hence to protect her may be Wei killed them.
dam. ... I knew Wei killed em cuz of something related to Lihea but was not expecting that. I bet Jia is feeling all types of confused and just broken mentally. but is Jia really Lihea's blood sister or n no not (not that it matters)